The general goal of the proposed research is to continue the investigation into mechanisms for control of blood flow in specific tissues. Five specific vascular beds will be used (skeletal muscle, subcutaneous adipose tissue, kidney, gut and cutaneous bed). These are histologically dissimilar and subserve different physiological functions. Rigidly controlled experimental conditions will be used so that responses produced can be identfied as being reflex in origin or secondary to a humoral or local mechanism. Each innervated but vascularly isolated tissue will be perfused with blood at constant flow. Reservoir blood will be used to insure constancy of blood constituents. Attention will be directed toward regulation of blood flow in adipose tissue, particularly as regards the effects of products of lipolysis (FFA, glycerol). Emphasis will be placed on the effects of autonomic receptors on lipolysis and metabolism and how these relate to changes in fat blood flow. Regulation of blood flow not only in adipose tissue but also in muscle, gut, kidney, and cutaneous bed will be evaluated during stimulation of selected CNS structures (hypothalamus, orbital cortex). These two CNS areas when stimulated produce opposite changes in blood pressure, cardiac output and heart rate. An examination can be made not only on blood flow changes in specific tissues but also on some of the mechanisms involved (e.g., adrenergic receptors, sympathetic withdrawal, alterations of baroreceptor function during CNS stimulation and any associated metabolic changes). These studies can be expanded to involve additional CNS structures. A more goal oriented study will be undertaken to investigate and methodically dissect the complex vascular adjustments that occur during acute experimental coronary artery occlusion. The theme throughout these investigations revolves around looking for multiple and interacting factors which comprise the general oscillating system involved in blood flow regulation, manipulating the experimental design to control one to allow for demonstration of anothr and apply these observations to a comprehensive evaluation of blood flow regulation in simulated clinical conditions (e.g., experimental coronary artery occlusion).